Additionally, the dwarf galaxies that dominate the faint end of the
Schechter-form LF have been found to have different internal structure
and kinematics than their brighter counterparts (Ferguson & Binggeli
1994). Their surface brightness profile is found to drop off as an
exponential less centrally concentrated than the 
dependence
of ellipticals; thus, dwarf ellipticals (dE) effectively
have larger core radii. In addition, the luminosity-velocity
dispersion relation for dE is 
, rather than 
as seen for the ellipticals. Consequently, dE have smaller
velocity dispersions than might be expected for their already low
luminosities. As lensing probability for a given lens drops with
rising core radius and is proportional to 
, the larger core radius and
smaller velocity dispersion of dE makes their contribution to lensing
statistics negligible. This effect can be accounted for by inserting
a exponential cutoff into the
effective LF of 
. Doing so reduces the
probability of lensing, particularly that producing small-angle
image separations.